Has anyone out there upgraded their ZF clutch and/or flywheel. What are your thoughts on billet flywheel vs. a more stout dual mass flywheel. Also any thoughts on ceramic vs. kevlar clutch. I'm not racing or pulling, I just need a clutch capable of towing with a tuner installed.Edited by: MOTO HEAD

Moto --


I would like to but haven't seen any after-market parts yet. Are you aware of any? If so, can you point me at them?


Thanks,


Tim

A few people are working on it. The big question is what's better, a billet flywheel or a heavy duty dualmass?

I emailed south bend clutch 2 weeks ago this is what they said





AT this time we are offering 2 styles of clutch discs only. One being Kevlar lined OEM disc and the other is a 6 paddle feramic design, both of which run $350. The rest of the components ie: flywheel and pressure plate, are not available to the aftermarket and would need to be purchased at the dealer if needed. These discs will offer approx. a 70% increase in torque capability.

Peter
800-988-4345 Edited by: jjgmc

Since the flywheel is the weak point, there isn't much point in buying an upgraded clutch until the aftermarket beefed up flywheels are available.

That's the same thing I was thinking. I just emailed them to see what they have. I will wait until they have both updated flywheel and clutch combo.

I just returned from the dealer. I've had slave cylinder problems and pedal squeaking problems. both replaced twice. now tech reps decline change outs until further tech bulletins and a correction. Also, my throwout bearing and "flexplate" (aka flywheel) are being replaced under warranty (http://www.dieselplace.com/forum/smileys/Big Smile.gif I am 1K beyond warranty but because of the clutch pedal problem and tech bulletins for the flywheel)!!


Wish someone would redesign the flexplate . . . .

The flywheel is covered under the 5 year 100000 mile warranty.

Dealer told me flywheel has been improved and already has a different part # than the flywheels that came on the 03 trucks. That's all I know.

I got my truck back with a new flexplate part number installed. The next day I passed a car with my juice and the clutch slipped and the pedal went hard. Doesn't happen in stock mode. What to do?

I took it in today and the service rep called the GM reg tech rep. They are going to install a transmission cooler AT NO COST TO ME http://www.dieselplace.com/forum/smileys/Clap.gif.


Hope this solves the hard pedal and slippage problem.

When that thing comes back let us know what cooler they use and what the part number is if it's a GM part.

Not a GM part. Aftermarket but will be installed by the Dealer. Puzzles me that they are cooling the tranny instead of the clutch hydraulic fluid. Also, they changed fluid from Dot 3 to Dot 4 because it handles better heat. http://www.dieselplace.com/forum/smileys/Confused.gif


I will let you know who the manufacturer is when I find out. Plus anything else of value . . . .

I found this piece of information on another board, maybe this will help solve the hard clutch issue...


NV241 manual shift transfercases were used behind all NV3500 transmissions. My ZF is not screwed up. Every one I have played with is the same….a bit noisier than the New Venture transmission. I did have a hard clutch pedal after driving on the highway for a while and found the release bearing/slave cylinder assembly was dragging on the input shaft sleeve. Cleaned up the sleeve with emery cloth and replaced release bearing assembly and corrected the jumpy grabby clutch engagement issue.


Later...

I found this piece of information on another board, maybe this will help solve the hard clutch issue...


NV241 manual shift transfercases were used behind all NV3500 transmissions. My ZF is not screwed up. Every one I have played with is the same….a bit noisier than the New Venture transmission. I did have a hard clutch pedal after driving on the highway for a while and found the release bearing/slave cylinder assembly was dragging on the input shaft sleeve. Cleaned up the sleeve with emery cloth and replaced release bearing assembly and corrected the jumpy grabby clutch engagement issue.


Later...









Well, this may solve some of the issues but mine is a result of slippage during aggressive acceleration. I can hear and feel the clutch slip. I think that the slippage creates heat that forces hydro fluid to expand and push pack on the clutch pedal. I am almost certain that if I had a decent flywheel that could hold up a extra heavy duty clutch & pressure plate, that there would be no slippage and hense no excessive heat and no 'back pressure' on the clutch pedal.